Today I will be posting a short article because I didn’t know I would be so tied up with the Live Support that I launched yesterday. Some of the cases were really tough but still managed to helped a few users and I am feeling really good about it. Anyway, have you ever noticed that there are times you’ll see weird characters such as %20, %3A and etc in webpages especially in URLs? These characters are called percent encoding and the 2 characters after the percentage sign actually represents a “reserved” character. Let’s do a simple test here if you don’t know what I am talking about. Open up Internet Explorer, type http://www.google.com/” in the URL and hit enter. Make sure you add a double quote after the slash. You will instantly see that the double quotes is being converted into %22.

Two days ago I received a copyright infringement notice and was asked to reply with the following subject RE%3A%20Copyright%20Infringement%20Notice%20ID%3A%20XXX%2DXXXXXXX or else my email would be treated as spam. I have done research on this before but I did not save the website that provided simply decoding to the percent encoding characters. When I really needed it again, I had to spend time looking up on the same thing that I’ve researched before. I am posting this out so I know where I can look it up in future and also hope that you guys can learn something new too.


There are 20 reserved characters including space ! * ‘ ( ) ; : @ & = + $ , / ? % # [ ] that has to be encoded only under certain circumstances. You can refer to the table below to manually convert the percent encoding to a character.

Surely I am not going to memorize all those hex codes, so here is a website that has an online tool for automatic URL Encoding and Decoding.

Simply enter the percent encoded URL to the form and hit the Decode button. Voila, the decoded text shows immediately.